This work deals with the range compression applied to MARSIS (Mars Radar for Subsurface and Ionosphere Sounding) data proposing a new approach to improve the S/N after matched filtering for both surface and subsurface responses. It will be also illustrated how the geometric term correction can be performed on a particular class of data previously not correctable according to surface/subsurface theoretical models. Finally, it will be demonstrated how a better estimation of the volume scattering can be obtained.